I am just curious as to why you want to remove the slip clutch. It looks like it is in good shape.
Sorry for taking so long to reply, kind of dropped this for a week or so.
Long story, but last year I bought a used KK II rototiller. The previous owner had cut the pto shaft pretty short, for the 8N he was using it on. Young kid, I don't think he really knew what he was doing.
Well, on my tractor, with the PEC system and a 4" PTO extender, the two sections of the PTO shaft would separate. So, there were a few options, and the easiest seemed to be to replace the PTO shaft. That was $219 new, you have to buy the whole thing, including the slipclutch, which as you judged was in good shape. Heck, it's like almost new, been used very little because the blades on the tiller still have yellow paint on them.
So, just recently I found a complete, BRAND NEW heavy duty short PTO shaft made for tillers, spreaders, and other PTO attachments that use a shorter PTO shaft. The only problem is this one is made to work with a shear bolt on the implement end, instead of the clutch. So, it's a "smooth bore", whereas the gear box on the tiller has 6 splines.
My plan is to see if I can remove the yoke end on the new shaft that uses the shear bolt, and replace with the yoke end (on the old, short shaft) that has the slip clutch. It *looks* like they will interchange. I got the new shaft for $50, so if this works it will be a sweet deal and get my rototiller going just in time for spring tilling.
If this doesn't don't work, then I am shafted!!

I will have a brand new, uncut, heavy duty PTO shaft that uses a shear bolt for sale, a used PTO shaft with slip clutch that is cut pretty short for sale, and guess I will be looking to buy a brand new PTO shaft from TSC for about $219. The proof is in the pudding though, and won't really know if it'll work until I get the u-joints out and try and swap ends and see if they will match up. I will try that later this week.
Btw, I got the slip clutch off today. I wound up having to hook the tiller up so I could lift it, and then rotate the shaft to get a good angle and drive it out with the punch & hammer. The tapered bolt came out with a few light taps with a punch and hammer. See my pictures I added. Will let you know if the two yokes will interchange or not. Cross your fingers, and thanks for the help fellows!!!
Here is the tapered bolt:
Here is the hole it came out of:
